This invention relates to an ink jet wherein the ink employed within the jet is of the phase change type which may be referred to as hot melt ink.
A phase change or hot melt ink of the type utilized in an ink jet is characteristically solid at room temperature. When heated, the ink will melt to a consistency so as to be jettable. A hot melt ink jet apparatus and method of operation are disclosed in copending application Ser. No. 610,627, filed May 16, 1984, which is assigned to the assignee of this invention. The hot melt ink may be jetted from a variety of apparatus including those disclosed in the aforesaid copending application.
When employing ink in a liquid state, the delivery of the ink is, of course, dictated by the liquid state. Typically, the ink is contained within a closed vessel of some sort prior to delivery to the ink jet. When employing hot melt ink, the solid state nature of the ink suggests different ink delivery techniques.
A variety of techniques have been suggested for delivery of hot melt ink in a solid state to an, ink jet apparatus. Copending application Ser. No. 660,656, filed Oct. 15, 1984, which is assigned to the assignee of this invention, discloses the use of replaceable cartridges of hot melt ink which are heated so as to melt and drain the ink from the cartridge to a suitable reservoir. The feeding of pellets from a carrier or cartridge are disclosed in copending application Ser. No. 660,657, filed Oct. 15, 1984, which is assigned to the assignee of this invention, and copending application Ser. No. 661,922, filed Oct. 16, 1984, which is also assigned to the assignee of this invention. Both of these applications disclose feeding of discreet pellets and the discharging of those pellets into a reservoir where melting may occur. Copending U.S. patent applications Ser. No. 660,655, filed Oct. 15, 1984, now U.S. Pat. No. 4,593,292, Ser. No. 661,701, filed Oct. 16, 1984, and Ser. No. 661,034, filed Oct. 15, 1984 all disclose the feeding of an elongated slab or stick of hot melt ink which is advanced and sequentially melted.